Optimizing Power for Remote Grids with Diesel, Wind, Solar, and Batteries

This patent describes a computer-based method for designing and operating independent power systems, called micro-grids, to balance cost, reliability, and environmental impact using a mix of diesel generators, wind turbines, solar panels, and energy storage batteries.

What it covers

The patent outlines a method for optimizing an independent micro-grid system, which includes diesel generators, wind generators, a photovoltaic array, and an energy storage battery. It works by first gathering device parameters for all these components. Then, a computer system uses a multi-objective genetic algorithm to find the best setup. This algorithm considers three main goals: minimizing total cost over the system's lifetime, reducing the chance of power outages (loss of load capacity), and lowering pollution levels. The method also uses a 'quasi-steady state simulation strategy' with two modes: a 'hard charging strategy' where diesel generators can charge the battery, and a 'power smooth strategy' where the battery only helps when diesel alone isn't enough. For example, it calculates how many diesel generators are needed at any moment, considering the current power demand, available renewable energy, and the battery's charge/discharge limits (Claim 1).

What it doesn't cover

• —Does not cover optimization methods that use algorithms other than a multi-objective genetic algorithm, specifically one based on NSGA-II.
• —Does not cover micro-grid systems that rely on different primary energy sources, such as hydropower or geothermal, instead of the specified diesel, wind, and photovoltaic combination.
• —Does not cover control strategies for energy storage batteries that do not include both a 'hard charging strategy' and a 'power smooth strategy' as defined.
• —Does not cover systems that fail to account for a 'preset spare capacity' to ensure the micro-grid's stability.
• —Does not cover optimization models that do not simultaneously consider the three specific objectives: total cost, loss of load capacity, and pollution level.

The clever bit

The clever part is the integrated multi-objective optimization using a genetic algorithm. It simultaneously balances conflicting goals—like saving money, keeping the lights on, and protecting the environment—while also factoring in complex operational details like diesel generator start-up modes and battery charging strategies, along with system stability requirements.

Why it matters

Independent micro-grids are crucial for providing reliable power to remote areas, islands, or military bases where connecting to a large central grid is impractical or too expensive. This patent offers a systematic way to design these systems, ensuring they are not only cost-effective but also reliable and less polluting. By optimizing the mix of renewable sources and traditional generators, it helps make off-grid power solutions more sustainable and widely deployable, especially in regions with limited infrastructure.

Real-world examples

• 1.Remote village power systems in developing countries
• 2.Island communities relying on local generation
• 3.Military bases in isolated locations
• 4.Off-grid industrial facilities
• 5.Emergency backup power for critical infrastructure